Re: [RFC][PATCH 1/2] tracing/ftrace: syscall tracing infrastructure

2009-03-16 Thread Frank Ch. Eigler
Hi - On Mon, Mar 16, 2009 at 05:45:26PM -0400, Mathieu Desnoyers wrote: [...] As far as I know, utrace supports multiple trace-engines on a process. Since ptrace is just an engine of utrace, you can add another engine on utrace. utrace-+-ptrace_engine---owner_process |

Re: [RFC][PATCH 1/2] tracing/ftrace: syscall tracing infrastructure

2009-03-16 Thread Frederic Weisbecker
On Mon, Mar 16, 2009 at 06:18:00PM -0400, Frank Ch. Eigler wrote: Hi - On Mon, Mar 16, 2009 at 05:45:26PM -0400, Mathieu Desnoyers wrote: [...] As far as I know, utrace supports multiple trace-engines on a process. Since ptrace is just an engine of utrace, you can add another

Re: Q: utrace-stopped utrace_report_jctl()

2009-03-16 Thread Oleg Nesterov
On 03/15, Roland McGrath wrote: Then we re-do this (well, almost) check under -siglock, } else if (task_is_stopped(target)) { if (!(target-utrace_flags UTRACE_EVENT(JCTL))) utrace-stopped = stopped = true; } But this is not nice. Let's

Re: utrace_set_events/utrace_control death/reap checks

2009-03-16 Thread Oleg Nesterov
On 03/15, Roland McGrath wrote: utrace_set_events: (utrace-death ((old_flags ~events) DEATH_EVENTS)) (old_flags ~events) DEATH_EVENTS) means the caller tries to clear DEATH/QUIESCE. Why this is not allowed? And why this is not allowed _only_ when the target runs

Re: [RFC][PATCH 1/2] tracing/ftrace: syscall tracing infrastructure

2009-03-16 Thread Oleg Nesterov
On 03/16, Mathieu Desnoyers wrote: utrace_add_engine() set_notify_resume(target); ok, so this is where the TIF_NOTIFY_RESUME thread flag is set. I notice that it is set asynchronously with the execution of the target thread (as I do with my TIF_KERNEL_TRACE thread flag). However, on